Ever since the shooting, there’s been a persistent rumor that Lanza
actually used two handguns to kill his victims—not the Bushmaster. I get
a lot of emails to this effect, and so I thought it would be worth my
while to lay out some facts. Adam Lanza did use the Bushmaster in the
Sandy Hook shootings, and anyone who says otherwise is wrong, wrong,
wrong.
My source for this is the Connecticut State Police, who apparently
were also tired of fielding questions about Lanza’s choice of weapons.
In January, they issued a news release to set things straight. Here’s the relevant part:

The shooter used the Bushmaster .223 to murder 20 children
and six adults inside the school; he used a handgun to take his own life
inside the school. No other weapons were used in this crime. This case
remains under investigation.